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~ 1140.3 129r 1996 c. 3
THE CURTIS REPORT
1996 SUPPLEMENT
ILLINOIS RIVER IRRIGATION TAILWATER
PROJECT
OKLAHOMA DEPARTMENT OF AGRICULTURE
PLANT INDUSTRY AND CONSUMER SERVICES
MAY 20 1997
This report- is named after James H. "Jim" Curtis for his lifelong
dedication to serving agriculture and protecting the environment. Jim was
instrumental in the initial development of this project. Through his efforts
and hard work, this project began as an idea and has evolved into a
mission. Today, with a strong spirit of mutual cooperation, the Nursery
Industry and the Oklahoma Department of Agriculture are committed to the
protection of the quality of the Illinois River.
.:
This report was compiled and written by Don R. Molnar, Ph. D. The samples were taken
by Saundra Osborn, Carol Phillips and -Sancho Dickinson. Carol Phillips and Sancho
Dickinson III helped review the report. Thanks to David Wheelock for construction of
the maps and Laurel Platt for assistance in getting this report printed. -
" i
EXECUTIVE SUMMARY
This is the 1996 Supplement to The 1992 Curtis Report on the Illinois River Irrigation
Tailwater Project that was started in 1989 as a result of an inquiry concerning the
irrigation tailwater leaving the property of nurseries along the Illinois River. The project
was directed toward limiting the concentration of nutrients and pesticides in the irrigation
tailwater return flow of the commercial nurseries by the use of BMP's and compliance
agreements.
Maintaining the water quality of this area is a very important criteria for preserving the
natural beauty of a scenic river, the potability of an important source of drinking water,
the recreational value of the river and lake, and the economy of the surrounding area.
Blue Valley Nursery was dropped from the project in 1996 due to no activity at this
location. If the nursery becomes active in the future then sampling of the irrigation
tailwater return flow will resume.
In 1996 Plant Industry and Consumer Services (PICS) continued sampling on a monthly
basis the' irrigation tailwater, the intake water, and the well water at Greenleaf Nursery,
Midwestern Nursery, and Park Hill Nursery. The parameters that were analyzed for in
the samples were Nitrate-Nitrogen (N03-N), Total Phosphorus (Total-P), and
Organochloride and Organophosphate pesticide residues. The Illinois River water was
also sampled both upstream and down stream from Greenleaf and Midwestern Nursery
and checked for the same parameters as the other sites.
Ammonia Nitrogen (NH4-N) samples were also taken at the nursenes this year.
Voluntary Compliance Agreements between each nursery and the Oklahoma State
Department of Agriculture were renegotiated and signed in late 1994. These established
an average Nitrate-Nitrogen concentration of 10.0 ppm (mgll) and an average Total-
Phosphorus concentration of 1.0 ppm (mg/l) in the irrigation tailwater of the nurseries
for 1996. The compliance agreement maximum, 15.0 ppm (mg/l) for N03-N and 1.50
ppm (mg/l) for Total-P, for individual samples was continued at 50% greater than the
yearly average. If any two consecutive samples are above the maximum allowed by the
compliance agreement the nurseries are required to evaluate their best management
practices toward the goal of lowering the concentrations.
The pesticide concentrations were set at 0.0 ppb. If a pesticide was detected in two
consecutive samples the nursery would stop using the pesticide until it could be used
without entering the irrigation tailwater return flow.
GREENLEAF NURSERY
Greenleaf Nursery is to be commended for their commitment to a clean environment by
the construction of retention basins for the total retention and reuse of their irrigation
tailwater return flow. Several basins have been completed to date.
Greenleaf Nursery's overall yearly average N03-N concentration increased from 6.99
mg/l in 1995 to 10.26 mg/l in 1996. The yearly average N03-N concentrations were
higher at tailwater sites IT-3a and IT-6 and lower at tailwater site IT-2 than in 1995.
Irrigation tailwater site IT-6 had N03-N concentrations exceeding the compliance
agreement maximum of 15.0 mg/l on four different sampling dates (three of these dates
were consecutive) after subtracting the intake water N03-N concentration. The elevated
N03-N concentrations were due to the movement of dirt during the construction of
retention basins and the use of different fertilizers in trying to solve a fertilizer
deficiency problem at the nursery.
The highest concentrations for the year occurred during the spnng and early summer
months.
Ammonia Nitrogen samples were taken once at two sites in 1996.
Greenleaf Nursery's overall yearly average Total-P concentration was 0.57 mg/l which is
0.26 mg/l lower than in 1995 and below the compliance agreement average of 1.00 rng/l.
No tailwater site exceeded the compliance agreement maximum in 1996. Irrigation
tailwater site IT-2 lowered their Total-P concentration from 1.29 mg/l in 1995 to 0.80
mg/l in 1996.
There were two (2) different pesticides detected in 1996 at the tailwater sites. Diazinon
was detected twice, in February and in August, at concentrations less than 2 ppb.
Oxadiazon was detected 11 times at concentrations from 1.56 ppb to 0.062 ppb. This
product has not been used by this nursery since 1990.
MIDWESTERN NURSERY
Midwestern Nursery is to be commended for maintaining the nutrient concentration In
their irrigation tailwater return flow below the compliance agreement average for the past
several years.
Midwestern Nursery had no consecutive samples that exceeded their compliance
agreement average for N03-N concentrations in 1996. The yearly average N03-N
concentration increased from 3.37 mg/l in 1995 to 4.38 mg/l (ppm) in 1996. This IS
below the compliance average of 10.0 ppm.
The Ammonia Nitrogen samples were taken once at two sampling sites In 1996.
The yearly average Total-P concentration remained about the same at all irrigation
tailwater sites in 1996. The yearly average Total-P concentration decreased from 0.62
mg/l in 1995 to 0.60 mg/l in 1996.
There was one pesticide, Oxadiazon detected .in 1996. The Oxadiazon was from the use
of a herbicide in 1995 that had 1 % Oxadiazon as a constituent. The use of that product
was suspended in August 1995.
PARK HILL NURSERY
Park Hill Nursery is to be commended for lowering the already low nutrient
concentrations in their irrigation tailwater return flow for 1996.
The N03-N concentration at Park Hill Nursery remained below the compliance
agreement average of 10.0 mg/l at all tailwater sites. The yearly N03-N concentration
decreased from 0.94 mg/I in 1995 to 0.76 mg/I in 1996.
The Ammonia Nitrogen sample was taken once at two sampling sites in 1996.
The yearly average Total-P concentration decreased from 0.36 mg/l in 1995 to 0.26 mg/l
in 1996.
Park Hill Nursery had no pesticides detected in its irrigation tailwater sites in 1996.
TABLE OF CONTENT
INTRODUCTION
SAMPLING RESULTS
MAP OF NURSERIES ON THE ILLINOIS RIVER
GREENLEAF NURSERY
Description of Sampling Sites
Figure GL-l Map of Greenleaf Nursery
Sampling Results - Nitrate-Nitrogen
Sampling Results - Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results - Pesticides
Summary
Figures GL-2 to GL-ll
MIDWESTERN NURSERY
Description -of Sampling Sites
Figure MW-l Map of Midwestern Nursery
Sampling Results - Nitrate-Nitrogen
Sampling Results - Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results - Pesticides
Summary
Figures MW-2 to MW-9
PARK HILL NURSERY
Description of Sampling Sites
Figure MW-l Map of Midwestern Nursery
Sampling Results Nitrate-Nitrogen
Sampling Results Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results Pesticides
Summary
Figures PH-2 to PH-9
1
1-2
3
4-22
4-5
6
7-9
9-10
10
11
12
13-22
23-36
23
24
25
26-27
27
27-28
28
29-36
37-50
37
38
39-41
41
42
42
42
43-50
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
Greenleaf Nursery N03-N & Total-P Sample Results for 1996
Midwestern Nursery N03-N & Total-P Sample Results for 1996
Park Hill Nursery N03-N & Total-P Sample Results for 1996
Ammonia-Nitrogen (NH4-N) Sample Results for 1996
Pesticide Sample Results for 1996
PAGES
6
5
4
1
16
11
LIST OF TABLES
TABLE PAGE
. GL-1 Description of Sampling Sites at Greenleaf Nursery. 4
GL-2 Average N03-N and TOTAL-P Concentration (ppm) for each
Sampling Site at Greenleaf Nursery from 1992 to 1996. 7
GL-3 The N03-N Concentration in Irrigation Tailwater Site IT-6
after Subtracting The Average N03-N Concentration of the
Two Intake Water Sites 9
GL-4 Pesticide Detection in Tailwater Return Flow at Greenleaf
Nursery for 1996. 11
MW-1 Description of Sampling Sites at Midwestern Nursery. 23
MW-2 Average N03-N and TOTAL-P Concentration for each Sampling
Site at Midwestern Nursery from 1992 to 1996. 25
PH-1 Description of Sampling Sites at Park Hill Nursery. 37,39
PH-2 Average N03-N and TOTAL-P Concentration (ppm) for each
Sampling Site at Park Hill Nursery from 1992 to 1996. 39
111
IV
LIST OF FIGURES
FIGURE PAGE
1 Map of the Illinois River Showing Location of Nurseries in
the Irrigation Tailwater Project. 3
GL-l Map of Greenleaf Nursery. 6
GL-2 Graph of Nitrate-Nitrogen Concentrations in Intake Water
Site IT-I at Greenleaf Nursery for 1994-1996. 13
GL-3 Graph of Nitrate-Nitrogen Concentrations in North
Intake Water Site IT-lb at Greenleaf Nursery for 1994-1996. 14
GL-4 Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-2 at Greenleaf Nursery for 1994-1996. 15
GL-5 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-3a at Greenleaf Nursery for 1994-1996. 16
GL-6 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-6 at Greenleaf Nursery for 1994-1996. 17
GL-7 Graph of Total Phosphorus Concentrations in Intake Water
IT-l at Greenleaf Nursery for1994-1996. 18
GL-8 Graph of Total Phosphorus Concentrations in North Intake
Water Site IT-lb at Greenleaf Nursery for 1994-1996. 19
GL-9 Graph of Total Phosphorus Concentrations in Tailwater Site
IT-2 at Greenleaf Nursery for 1994-1996. 20
GL-lO Graph of Total Phosphorus Concentrations in Tailwater Site
IT-3a at Greenleaf Nursery for 1994-1996. 21
GL-ll Graph of Total Phosphorus Concentrations in Tailwater Site
IT-6 at Greenleaf Nursery for 1994-1996 22
MW-l Map of Midwestern Nursery. 24
MW-2 Graph of Nitrate-Nitrogen Concentrations in Intake
Water Site IT-28 at Midwestern Nursery for 1994-1996 29
MW-3 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-23 at Midwestern Nursery for 1994-1996 30
MW-4 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-25 at Midwestern Nursery for 1994-1996 31
FIGURE
MW-5
MW-6
MW-7
MW-8
MW-9
PH-l
PH-2
PH-3
PH-4
PH-5
PH-6
PH-7
PH-8
PH-9
LIST OF FIGURES
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-27 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Intake Water
Site IT-28 at Midwestern Nursery for 1994-1996.
Graph of Total Phosphorus Concentrations in Tailwater
Site IT-23 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater
Site IT-25 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-27 at Midwestern Nursery for 1994-1996
Map of Park Hill Nursery.
Graph of Nitrate-Nitrogen Concentrations in Intake Water
Site IT-16a at Park Hill Nursery for 1994-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-15 at for 1995-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater Site.
IT-18a at Park Hill Nursery for 1995-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-19b at Park Hill Nursery for 1994-1996.
Graph of Total Phosphorus Concentrations in Intake Water
Site IT-16a at Park Hill Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-15 at Park Hill Nursery for 1995-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-18a at Park Hill Nursery for 1995-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-19b at Park Hill Nursery for 1994-1996
v
PAGE
32
33
34
35
36
38
43
44
45
46
47
48
49
50
INTRODUCTION
This is the 1996 Supplement to the 1992 Curtis Report of the Illinois River Irrigation
Tailwater Project involving Greenleaf Nursery, Midwestern Nursery and Park Hill Nursery
that are in operation along the Illinois River and Lake Tenkiller in Cherokee County and
the Oklahoma State Department of Agriculture, Plant Industry and Consumer Services
(PICS).
In 1996, PICS continued monitoring the nurseries by taking samples on a monthly basis
and analyzing the samples for the same parameters, Nitrate-Nitrogen (N03-N), Total
Phosphorus (Total-P) and pesticides, which has been done monthly since 1989.
Beginning in 1995 Ammonia-Nitrogen (NH4--N) was checked periodically to determine a
base level. This was continued in 1996.
Blue Valley Nursery was dropped from the project in 1996 due to inactivity at this
location. If the nursery becomes active in the future then sampling of the irrigation
tailwater return flow will resume.
In 1994, PICS negotiated with each of the nurseries a new compliance agreement which
resulted in lower limits on the nitrate-nitrogen concentration allowed in the irrigation
tailwater return flow of the nurseries.
The 1994 Compliance Agreement with each nursery set the following limits for 1996:
Yearly Average N03-N 10.0 ppm (mg/l)
Individual Sample Maximum N03-N No more than 50% above the
compliance agreements yearly
average on two consecutive
samples, 15.00 ppm (mg/l)
Yearly Average Total-P 1.0 ppm (mg/I)
Individual Sample Maximum No more than 50% above the
compliance agreements yearly
average on two consecutive
samples, 1.5 ppm (mg/l)
Ammonia-Nitrogen NH4-N Checked periodically to
determine base level.
Pesticides 0.0 ppb - Suspend use of a~y
detected after verification In
follow up sample.
1
SAMPLING RESULTS
The sampling results for irrigation tailwater runoff are discussed for each specific
nutrient and pesticide in relation to their compliance agreement with OSDA. The
sample results were looked at under the following conditions:
1. The only statistical calculations conducted on the results were averages.
2. The N03-N and Total-P concentrations of the intake water were not
subtracted from the tailwater samples except where consecutive samples were
at or above the individual sample maximum.
3. Results considered to be outside the data range were discarded.
4. All analysis results are reported in milligrams per liter (mg/l) (same as parts
per million-ppm) for N03-N and Total-P and parts per billion (Ppb) for
pesticides.
5. On numerous occasions, duplicate samples were taken or the lab ran the
analysis more than once. When this occurred the higher sample results were
reported.
6. The owner or manager of each nursery was notified of sample results on a
monthly basis.
7. The pesticide samples that showed a positive detection are listed in tables in
the body of the report. The name of the pesticide is the common name not
the trade name.
8. Graphic presentations concerning intake and irrigation tail water return flow
sampling data are provided in the report. Sampling data for all other sites
are located in the Appendices.
9. Sampling results reported from the lab as 0.0 are below the detectable limit
of 0.20 mg/l (ppm) for Nitrate-Nitrogen (N03-N) and Ammonia-Nitrogen
(NH4-N); 0.02 mg/l (ppm) for Total Phosphorus; 0.0100 ug/l (ppb), for
Organophosphate pesticides and 0.0010 ug/l (ppb) for Organochloride
pesticides.
2
-,G--.t'bson
-- Lake
NA
o 2 3 4 5 Miles
Figure 1
Map of the Illinois River
Showing Location of
Nurseries in the Irrigation
Tailwater Project
10
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f . $"
.( ~
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~~ Midwestern
Tahlequah ~Nurse
62
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~- -- 'Sewage (
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Park 'Ft11L-/
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Lake
Tenkiller,
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51.r--_---'
GREENLEAF NURSERY
Greenleaf Nursery is approximately 460 acres, located on hilly land directly adjacent to
Lake Tenkiller on Oklahoma State Highway 82 in Cherokee County.
Irrigation water is pumped from the lake and applied to container grown trees and
shrubs through a stationary overhead sprinkler system.
Fertilization is done mostly by using plastic encapsulated slow release type fertilizer
which is either mixed into the soil media or applied to the top of the soil by hand.
In 1996 Greenleaf Nursery continued the construction of retention basins with pumping
facilities in order to recycle their irrigation tailwater. This construction has resulted in a
large amount of dirt and rock being moved, which may have contributed to some of the
elevated levels of nitrate-nitrogen in some irrigation tailwater return flow samples.
Figure GL-1 is a map showing the sampling sites at Greenleaf Nursery for 1996.
DESCRIPTION OF SAMPLING SITES.
Table GL-1 lists and describes the sampling sites at Greenleaf Nursery for 1996.
TABLE GL-l: Description of Sampling Sites at Greenleaf Nursery
SITE DESCRIPTION
IT-1 Main water intake site. Located on the southeast side of the nursery
and down the bank to Lake Tenkiller. The samples are taken from the
area around the float where the pumps are located.
IT-1b Second intake site situated on the northeast side of the nursery down
the bank to Lake Tenkiller. The samples are taken from around the
float where pumps are located.
IT-2 Irrigation tail water runoff site located on the southeast side of the
nursery approximately 200 feet south of the main intake float on Lake
Tenkiller. The samples are taken as the water leaves the nursery
property.
IT-3a Irrigation tailwater site located at the detention basin near the main
entrance to the nursery. The samples are taken down the dam
embankment where the overflow pipe empties.
IT-4 Ephemeral stream on the northeast side of the main container area.
This site is located along the dirt road on the north edge of the
nursery. The samples are taken near the pipe after going under the
road and before entering Greenleaf Nursery's property.
4
TABLE GL-l: Description. of Sampling Sites at Greenleaf Nursery Con't.
IT-5 Ephemeral stream entering the nursery near the upper detention basin
from the outside. This site is located on the dirt road along the north
boundary of Greenleaf Nursery's property. The samples are taken near
pipe that goes under the road and before entering the nursery's
property. Sampled when sufficient runoff is present
IT-6 Irrigation tailwater runoff site located on the southeast side of the
nursery. The samples are taken 100 ft. below the last confluence of
nursery tailwater runoff.
IT-11 Well is located south of the propagation greenhouses near the entrance
to Greenleaf Nursery. The samples are taken from hose bibb inside
the well house.
5
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~~
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~
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Greenleaf
Nursery
400 Acres
S19 T15N R23E
/(
!
j
I! \,
\
i
I\
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N A
o 0.5 1 Miles ••••••••••••••~===============I
Figure GL-1
Map showing the location of the sampling sites at Greenleaf Nursery for 1996.
SAMPLING RESULTS
Sample results for site IT-4 and site IT-5 see Appendix - A.
NITRATE-NITROGEN (N03-N)
The 1994 compliance agreement with Greenleaf Nursery set the yearly average N03-N
concentration for 1996 at 10.0 ppm (mg/l) and the maximum limit (50% greater than the
yearly average) at 15.0 ppm (mg/l) on two consecutive sampling dates after subtracting
the intake water N03-N concentration.
The N03-N concentration in 1996 was lower than in 1995 at site IT-2 and higher at
the other two tailwater sites. Site IT-6 average of 13.12 mg/l exceeds the compliance
agreement average of 10.00 ppm (mg/l). The highest concentrations continued to occur
during the late spring and summer months. (Fig. GL-4, GL-5, and GL-6)
There were three consecutive samples that exceeded the compliance agreement maximum
of 15.00 mg/l in 1996; after subtracting the average of the two intake water sites N03-
N concentrations. These occurred at site IT-6 in August, September and October with
29.26 mg/l (31.6 - 2.34), 16.43 rng/l (16.43 - 0.0) and 21.54 mg/l (21.88 - 0.34) respectively
(Table - GL-3). Greenleaf Nursery was contacted to find out the cause of these
elevations. The elevated N03-N concentrations were due to the movement of dirt
during the construction of retention basins in addition to the use of new fertilizer
products and in correcfing a fertilizer deficiency problem.
The yearly average N03-N concentration in the tailwater sites increased to 10.26 mg/l 10
1996 (Table GL-1). This is an increase of 46.78% from the 1995 concentration.
TABLEGL-2: Average N03-N and TOTAL-P Concentrations (mg/l) for each
Sampling Site at Greenleaf Nursery from 1992 to 1996.
SAMPLING SITE N03-N mg/l TOTAL-P mg/l
92 93 94 95 96 92 93 94 95 96
IT-1 1.08 1.11 1.10 0.81 1.18 0.10 0.11 0.16 0.09 0.12
IT-1b 0.97 1.04 0.08 0.11
IT-2 8.58 6.24 10.53 10.13 8.65 1.13 1.09 1.37 1.29 0.8
IT-3a 15.65 11.85 6.97 6.56 9.01 0.46 0.61 0.43 0.68 0.51
IT-6 14.48 9.30 8.57 4.27 13.12 0.44 0.60 0.44 0.51 0.41
IT-II 0.20 0.42 0.15 0.44 0.62 0.12 0.03 0.07 0.05 0.03
IT-12 16.68 12.09 ---- 1.18 0.66 -- --
Tailwater
Yearly Avg. 13.85 9.87 8.69 6.99 10.26 0.80 0.74 0.75 0.83 0.57
Compliance
Ag.Avg. 28.0 18.5 15.5 14.5 10.00 1.0 1.0 1.0 1.0 1.0
7
Site IT-l- Intake
The N03-N concentrations at site IT-1 ranged from 0.0 mg/l in October (below the
detectable limit of 0.2 mg/l) to 2.34 mg/l in August (Fig. GL-2 and Appendix - A).
The yearly average N03-N was 1.18 mg/I (Table GL-2).
Site IT-lb - SecondIntake
The N03-N concentrations at site IT-lB ranged from 0.0 mg/l (below the detectable
limit of 0.2 mg/l) in July to 2.33 mg/l in December (Fig. GL-3 and Appendix - A) with
a seasonal low occurring in the summer months.
The yearly average N03-N was 1.04 mg/l (Table GL-2).
Site IT-2.
The N03-N concentrations at site IT-2 (the waterfall) ranged from 1.57 mg/l in October
to 19.74 mg/l in May. Two samples, one taken in May and the other taken in August
were above 15.0 mg/l (the compliance agreement average) (Fig. GL-4 and Appendix-
A). However, these were not consecutive samples.
The yearly average N03-N concentration decreased from 10.13 rng/l in 1995 to 8.65
mg/l in 1996 (Table GL-2 and Fig. GL-4). This is a decrease of 14.61% from 1995.
Site IT-3a
The N03-N concentration for site IT-3a ranged from a low of 0.0 mg/l (below the
detectable limit of 0.2 mg/l) in June to a high of 14.64 mg/l in July (Fig. GL-5 and
Appendix - A). No sample exceeded the compliance agreement maximum of 15.0 mg/I.
The yearly average N03-N concentration increased from 6.97 mg/l in 1995 to 9.01 mg/l
in 1996 (Table GL-2 and Fig. GL-5) This is an increase of 37.35% from the 1995
yearly average. However, this was still below the compliance agreement average of 10.0
mg/I.
Site IT-6
The N03-N concentration for site IT~ ranged from a low of 0.0 mg/l (below the
detectable limit of 0.2 mg/I) in February to a high of 33.47 mg/l in June (Fig. GL~
and Appendix - A). There were three samples that exceeded the compliance agreement
maximum of 15.0 ppm (mg/I) on consecutive dates after subtracting the intake waters
N03-N concentration (Table GL-3).
As discussed earlier these elevations were due to movement of dirt in the construction of
detention basins, and the use of different fertilizers in trying to solve a fertilizer
deficiency problem.
The yearly average N03-N concentration increased from 4.27 mg/l in 1995 to 13.12 mg/l
in 1996 (Table GL-2 and Fig. GL~). This represents a 207% increase from the 1995
yearly average.
8
TABLE GL-3 The N03-N Concentration in Irrigation Tailwater Site
IT-6 after Subtracting The Average N03-N Concentration of the
Two Intake Water Sites.
DATE IT-16 mg/l Avg. Intake mg/l Adjusted mg/l
5/20 15.62 1.73 13.89 below compliance maximum
6/25 33.47 0.25 33.22 above compliance maximum
8/27 31.6 2.34 29.26 above compliance maximum
9/9 16.43 a 16.43 above compliance maximum
10/15 21.88 0.34 21.54 above compliance maximum
Site IT-U WATER WELL
The N03-N concentrations ranged from a low 0.34 mg/l in September to a high of 1.19
mg/l in October (Appendix - A).
The yearly average was 0.62 mg/l in 1995 (Table GL-2)
TOTAL PHOSPHORUS (TOTAL-P)
The 1994 compliance agreement set a yearly average Total-P concentration of 1 mg/l
and a maximum limit of not greater than 50% above the yearly average or 1.5 mg/l on
two consecutive sampling dates after subtracting the intake water Total-P concentration.
All irrigation tailwater sites had a lower yearly average Total-P concentration in 1996
than 1995. Also, no site exceeded the compliance agreement average of 1 ppm (mg/l).
Greenleaf Nursery's overall yearly average Total-P concentration for irrigation tailwater
sites for 1996 is 0.57 mg/l which is 0.26 mg/l or 31% lower than the 0.83 mg/l in
1995.
Site IT-l
The Total-P concentration at the first intake site ranged from 0.02 mg/l in October to
0.31 mgll in November. No sample was taken in March (Fig. GL-7 and Appendix-A).
The yearly average is 0.12 mg/l (Table GL-2 and Fig. GL-7).
Site IT-IB
The Total-P concentration at the second intake site ranged from 0.02 mg/l in March to
0.50 mg/l in November (Fig. GL-8, Appendix - A). The yearly average is 0.11 mg/l
(Table GL-2 and Fig. GL-8).
9
Site IT-2
The Total-P concentration at irrigation tailwater site IT-2 ranged from a low of 0.28
mg/l in November to a high of 1.18 mg/l in March (Fig. GL-9 and Appendix - A).
The yearly average concentration for Total-P is 0.80 mg/I. This is below the
compliance agreement average of 1.0 mg/l (Table GL-2 and Fig. GL-9). This represents
a 38 % decrease from 1995.
Site IT-3a
The Total-P concentration at irrigation tailwater site IT-3a ranged from a low of 0.0
mg/l (below the detectable limit of 0.02 mg/l) in June to a high of 0.80 mg/l in April
(Fig. GL-lO and Appendix - A).
The yearly average concentration for Total-P is 0.51 mg/l which is below the
compliance agreement average of 1.00 mg/l (Table GL-2 and Fig. GL-lO). This
represents a decrease of 25% from the 1995 average of 0.68 mg/l.
Site IT~
The Total-P concentration at irrigation tailwater site IT-6 ranged from a low of 0.02
mg/l in March to a high of 1.24 mg/l in April. (Fig. GL-ll and Appendix - A) These
are below the compliance agreement maximum of 1.5 mg/l .
The yearly average concentration for Total-P is 0.41 mg/l (Table GL-2,). This is a
decrease of 20 % from the 1995 average of 0.51 mg/l.
Site IT-U Water Well
The Total-P ranged from a low of 0.0 mg/l (below the detectable limit of 0.02 mg/l) in
May to a high of 0.13 mg/l in October (Appendix - A). The yearly average was 0.05
mg/l.
AMMONIA-NITROGEN NH4-N
Ammonia Nitrogen (NH4-N) was checked once this year at site IT-1 and IT-6 There
has not been any maximum NH4-N concentrations set for the nurseries at this time.
Samples were taken during the primary irrigation season of April to September.
Site IT-l
One sample was taken In August with an NH4-N concentration of 0.36 mg/l (Appendix
D)
Site IT~
One sample was taken at this site. The NH4-N concentration was 9.44 mg/l in August
(Appendix D).
10
PESTICIDES
Greenleaf Nursery had Diazinon and Oxadiazon detected at irrigation tailwater site IT-2
and only Oxadiazon at site IT-3a and IT-6 in 1996. Table GL-4 lists the pesticides
detected, the date and site of the detection, and the concentration detected (Appendix E).
TABLE GL-4: Pesticide Detections in TailwaterReturn Flow at
Greenleaf Nursery For 1996
SITE DATE SAMPLE # COMMON NAME CONCENTRATION
in Parts Per
Billion (ppb)
IT-2
02-26-96 SO-477-P DIAZINON 1.907
08-27-96 SO-136-P DIAZINON 1.69
05-20-96 SO-686-P OXADIAZON 1.56
06-25-96 SO-796-P OXADIAZON 0.192
07-22-96 SO-016-P OXADIAZON 0.107
08-27-96 SO-27-96 OXADIAZON 0.979
IT-3a
02-26-96 SO-487-P OXADIAZON 0.977
04-22-96 SO-615-P OXADIAZON 0.85
05-20-96 S0-698-P OXADIAZON 0.56
08-27-96 SO-145-P OXADIAZON 0.471
IT-6 05-20-96 SO-692-P OXADIAZON 0.21
06-25-96 SO-802-P OXADIAZON 0.062
08-27-96 SO-138-P OXADIAZON 1.048
OXADIAZON
Oxadiazon was detected at all three sites in 1996. Four times at irrigation
tailwater site IT-2 and IT-3a, and three times at site IT-6. The concentration
ranged from 0.062 ppb in June at site IT-6 to 1.56 ppb in May at site IT-2
(Table GL-4 and Appendix E). This product has not been used by this nursery
since 1990.
DIAZINON
Diazinon was detected twice, February and August, at site IT-2 in 1996. Follow
up sampling did not detect any diazinon in the irrigation tailwater flow samples
(Table GL-4 and Appendix E).
11
SUMMARY
The 1994 compliance agreement lowered the yearly average N03-N concentration from
14.5 ppm (mg/l) in 1995 to 10.0 ppm (mg/I) in 1996. The maximum limit was lowered
to 15.0 ppm (mg/I) (50% greater than the yearly average on two consecutive sampling
dates after subtracting the intake water N03-N concentration) from the 21.75 ppm (mg/I)
in 1995.
The yearly average N03-N concentration decreased at tailwater site IT-2 and increased
at sites IT-3a and IT-6.
In 1996 the yearly average N03-N concentration increased from 6.99 mg/I in 1995 to
10.26 mg/I. This is an increase of 46.8 %.
Greenleaf Nursery had eight samples in 1996 that exceeded the compliance agreement
maximum for individual samples in regard to the N03-N concentrations.
Site IT-6 had N03-N concentrations exceeding the compliance agreement maximum of
15.0 mg/I on four (4) different sampling dates (three of these were consecutively) after
subtracting the intake water N03-N concentration). Site IT-3a had no samples that
exceeded the compliance agreement maximum. These elevations were due to movement
of dirt in the construction of detention basins, and the use of different fertilizers in
trying to solve a fertilizer deficiency problem.
Ammonia Nitrogen (NH4-N) samples were taken once at two sampling sites in 1996.
The average Total-P concentration was lower at all irrigation tailwater sites in 1996.
The overall average Total-P decreased from 0.83 mg/l in 1995 to 0.57 rng/l in 1996. This
is a decrease of 31.3%.
Site IT-2 lowered the Total-P concentration from 1.29 mg/l to 0.8 mg/l, a reduction of
38 % from the 1995 concentration.
There were two (2) different pesticides detected in 1996 in samples from the three
tailwater sites (Appendix E). Oxadiazon was detected 11 times at concentrations from
1.56 ppb to 0.062 ppb. This product has not been used by this nursery since May
1990. Diazinon was detected twice at site IT-2 at concentrations less than 2 ppb.
12
100
90
80
::::: 70 Cl
E
Wz 60 e0
a:
I- 50
Z,W
I<-t: 40 a:
t:
z 30
20
10
0
IT-l
• SAMPLE
-
- - - - - - - - - .- - - • - . co
Ol C:m -.,
ccop
"-3.,
SAMPLING DATES 1994-1996
Figure GL-2 Graph of the Nitrate-Nitrogen Concentration in the Intake Water Site IT-l at Greenleaf
Nursery for 1994-1996
100
90
80 ---
::C:::l 70
E
z W 60 o
0a:
!::: 50
zIW
aI«-: 40
!:::
z 30 --
20
10
IT-lb
• SAMPLE
-I--------~------~-------------------------~-----------------------------------1
0----- io
0> C-<--tI,
- - - - - - l!) '1' -:-5-,
<0
0> C-<--tI,
SAMPLING DATES 1994-1996
Figure GL-3 Graph of the Nitrate-Nitrogen Concentration in North Intake Water Site IT-lb at
Greenleaf Nursery for 1995-1996
IT-2
--SAMPLE COM MAX - - - COM AV - - YEARLY AV
100r------------------------------------------------------------------------------------------,
90 -----------------
,O~---------------------------------------------OJ ~
E
Z 0
W
C!I o
O!= CO~-----------------------------------------------------~
Z•W
<~t: O~---------------------------
~OC
Z 0 -1-----------
80
._--- .•.•..... _-
20~-------
10 .••••••-"'-
,
- - - - . - ... '\. - -- ---------------
l!)
C1> C:
.<..IS.,
<0
C1> C:
..<.I.S,
SAMPLING DATES 1994-1996
Figure GL-4: Graph of the Nitrate-Nitrogen Concentration in Irrigation Tailwater Site IT-2 at
Greenleaf Nursery for 1994-1996
IT-3a
•• SAMPLE - - COM MAX - - - COM AV - - YEARLY AV
100
90
80
::::: 70 Cl
Ez
60 W(
!)0
cr.
!:: 50 zIWI
c«r-. 40
!:: z 30
20
10
0
'<t
OJ
IC
CU
-:l
- - -
-------------. -
••
L()
OJ
IC
CU
-:l
to
OJ
IC
CU
-:l
to
.O..!J.
::J
-:l
SAMPLING DATES 1994-1996
Figure GL-5 Graph of the Nitrate-Nitrogen Concentration in Irrigation Tailwater Site IT-3a at
Greenleaf Nursery for 1994-1996
IT-6
_SAMPLE COM MAX COMAV - - YEARLY AV
100-r-----.---------.---- .--------
90+------------------------------------------------~
80
, 70~--------------------------------------------------------------------~ Cl
Ez
60+---------------------------------------------------------------------~ Wooa
:~
50+---------------------------------------------------------------~
ZIW
~ 40+-----------------------------------------------------------------~ ~a
:
~z 30+-------------------------------------
O~~~~~~~~~~~~~~~~_+~~~~~~~~~~~~~~--~~~~~~~~~~~~~
~C:
-t1,l
- - .• - - 20+----------------------------------------------------~~----------_4.---~
------------- ... ~ ---- --~- - -----
10~---_=~--_-~------_---------------------------------------
ll)
Ol C:
-t1,l
<D
Ol C:
-t1,l
SAMPLING DATES 1994-1996
Figure GL-6 Graph of the Nitrate-Nitrogen Concentration in Irrigation Tailwater Site IT-6 at
Greenleaf Nursery for 1994 to1996
=a, 6
E
IT-l
• SAMPLES
10
--
-•I___ - - - .- - - .-
9
8
7
3
2
o
co
0> C:
-el,l
to
0> C:
-el,l
SAMPLING DATES 1994-1996
Figure-GL-7 Graph of the Total-P Concentration in Intake Water Site IT-l at Greenleaf
Nursery for 1994-1996
IT-lb
• SAMPLES
10
-
- - - - - L
9
8
7
=a, 6
E
.~..J 5 «I- Io- 4
3
2
o
L!)
oCr.
-«,l
<0
Ol C.
-«,l
SAMPLING DATES 1995-1996
Figure GL-8 Graph of the Total-P Concentration in Intake Water Site IT-lb at Greenleaf Nursery
for 1994-1996
'§, 6
E
Il..
~ 5
~o•...4
IT-2
_SAMPLES - - COMP-MAX - -COMP-AV - - YEARLY-AV
10
-
-
=: . i--- - .- -- ---------_ .. - ""' . -- . ----- .•... - -- - - - •.... -- .'.-. --.- -----, --- .- - - - - - - -- - -If -- ---------------- I -- ~......----- .----.--.....--. • • I.I I 111.1.1
9
8
7
3
2
U')
(j)
C::
-ct,l
<0
(j)
C::
-ct,l
U') q>
"-S,
SAMPLING DATES 1994-1995
Figure GL-9 Graph of the Total-P Concentration in Irrigation Tailwater Site IT-2 at Greenleaf Nursery
for 1994-1996
IT-3a
_SAMPLES - - COMP-MAX - -COMP-AV - - YEARLY-AV
10 ,------ ---
7~---------
9 ~---------
8-·~---------------------------------------------~
~ 6 -1--------
E e,~
5~-------------------------
~o~4~--------------------------------------------~
3~--------------------------------------------~
2~--------------------------------------------~
SAMPLING DATES 1994-1996
Figure GL-I0 Graph of the Total-P Concentration in Irrigation Tailwater Site IT-Sa at Greenleaf
Nursery for 1994-1996
IT-6
- SAMPLES - - COMP-MAX - -COMP-AV - - YEARL Y-AV
10r--------------------------------------------------------------------------------------------------,
91----------------------
3 t-----
8-1--------------------------------------------------------------------------------------------------_1
7~-------------------------------------------------------------------------------------------------~
~6~---------------------------------------------------------------------------------------------------1
E
~ 5 t-----------------------------------------------------------------------------------------------~--...J ~
~g
4+--------------------------------------------------------------------------------------------------~
2~--------------------------------------------------------------------------------------------------~
O+-~~~~~~~~~~~~--~~~~~~~~~~~~~~~~~~~~~~--~~~~~~~~~~~~~ "<t-
O> -rCo,
- -- --
L!) ~-"S,
(0
0> -rCo,
L!)
0>
-rCo,
SAMPLING DATES 1994-1996
Figure GL-ll Graph of the Total-P Concentration in Irrigation Tailwater Site IT-6 at Greenleaf
Nurserv for 1994-1996

~ 1140.3 129r 1996 c. 3
THE CURTIS REPORT
1996 SUPPLEMENT
ILLINOIS RIVER IRRIGATION TAILWATER
PROJECT
OKLAHOMA DEPARTMENT OF AGRICULTURE
PLANT INDUSTRY AND CONSUMER SERVICES
MAY 20 1997
This report- is named after James H. "Jim" Curtis for his lifelong
dedication to serving agriculture and protecting the environment. Jim was
instrumental in the initial development of this project. Through his efforts
and hard work, this project began as an idea and has evolved into a
mission. Today, with a strong spirit of mutual cooperation, the Nursery
Industry and the Oklahoma Department of Agriculture are committed to the
protection of the quality of the Illinois River.
.:
This report was compiled and written by Don R. Molnar, Ph. D. The samples were taken
by Saundra Osborn, Carol Phillips and -Sancho Dickinson. Carol Phillips and Sancho
Dickinson III helped review the report. Thanks to David Wheelock for construction of
the maps and Laurel Platt for assistance in getting this report printed. -
" i
EXECUTIVE SUMMARY
This is the 1996 Supplement to The 1992 Curtis Report on the Illinois River Irrigation
Tailwater Project that was started in 1989 as a result of an inquiry concerning the
irrigation tailwater leaving the property of nurseries along the Illinois River. The project
was directed toward limiting the concentration of nutrients and pesticides in the irrigation
tailwater return flow of the commercial nurseries by the use of BMP's and compliance
agreements.
Maintaining the water quality of this area is a very important criteria for preserving the
natural beauty of a scenic river, the potability of an important source of drinking water,
the recreational value of the river and lake, and the economy of the surrounding area.
Blue Valley Nursery was dropped from the project in 1996 due to no activity at this
location. If the nursery becomes active in the future then sampling of the irrigation
tailwater return flow will resume.
In 1996 Plant Industry and Consumer Services (PICS) continued sampling on a monthly
basis the' irrigation tailwater, the intake water, and the well water at Greenleaf Nursery,
Midwestern Nursery, and Park Hill Nursery. The parameters that were analyzed for in
the samples were Nitrate-Nitrogen (N03-N), Total Phosphorus (Total-P), and
Organochloride and Organophosphate pesticide residues. The Illinois River water was
also sampled both upstream and down stream from Greenleaf and Midwestern Nursery
and checked for the same parameters as the other sites.
Ammonia Nitrogen (NH4-N) samples were also taken at the nursenes this year.
Voluntary Compliance Agreements between each nursery and the Oklahoma State
Department of Agriculture were renegotiated and signed in late 1994. These established
an average Nitrate-Nitrogen concentration of 10.0 ppm (mgll) and an average Total-
Phosphorus concentration of 1.0 ppm (mg/l) in the irrigation tailwater of the nurseries
for 1996. The compliance agreement maximum, 15.0 ppm (mg/l) for N03-N and 1.50
ppm (mg/l) for Total-P, for individual samples was continued at 50% greater than the
yearly average. If any two consecutive samples are above the maximum allowed by the
compliance agreement the nurseries are required to evaluate their best management
practices toward the goal of lowering the concentrations.
The pesticide concentrations were set at 0.0 ppb. If a pesticide was detected in two
consecutive samples the nursery would stop using the pesticide until it could be used
without entering the irrigation tailwater return flow.
GREENLEAF NURSERY
Greenleaf Nursery is to be commended for their commitment to a clean environment by
the construction of retention basins for the total retention and reuse of their irrigation
tailwater return flow. Several basins have been completed to date.
Greenleaf Nursery's overall yearly average N03-N concentration increased from 6.99
mg/l in 1995 to 10.26 mg/l in 1996. The yearly average N03-N concentrations were
higher at tailwater sites IT-3a and IT-6 and lower at tailwater site IT-2 than in 1995.
Irrigation tailwater site IT-6 had N03-N concentrations exceeding the compliance
agreement maximum of 15.0 mg/l on four different sampling dates (three of these dates
were consecutive) after subtracting the intake water N03-N concentration. The elevated
N03-N concentrations were due to the movement of dirt during the construction of
retention basins and the use of different fertilizers in trying to solve a fertilizer
deficiency problem at the nursery.
The highest concentrations for the year occurred during the spnng and early summer
months.
Ammonia Nitrogen samples were taken once at two sites in 1996.
Greenleaf Nursery's overall yearly average Total-P concentration was 0.57 mg/l which is
0.26 mg/l lower than in 1995 and below the compliance agreement average of 1.00 rng/l.
No tailwater site exceeded the compliance agreement maximum in 1996. Irrigation
tailwater site IT-2 lowered their Total-P concentration from 1.29 mg/l in 1995 to 0.80
mg/l in 1996.
There were two (2) different pesticides detected in 1996 at the tailwater sites. Diazinon
was detected twice, in February and in August, at concentrations less than 2 ppb.
Oxadiazon was detected 11 times at concentrations from 1.56 ppb to 0.062 ppb. This
product has not been used by this nursery since 1990.
MIDWESTERN NURSERY
Midwestern Nursery is to be commended for maintaining the nutrient concentration In
their irrigation tailwater return flow below the compliance agreement average for the past
several years.
Midwestern Nursery had no consecutive samples that exceeded their compliance
agreement average for N03-N concentrations in 1996. The yearly average N03-N
concentration increased from 3.37 mg/l in 1995 to 4.38 mg/l (ppm) in 1996. This IS
below the compliance average of 10.0 ppm.
The Ammonia Nitrogen samples were taken once at two sampling sites In 1996.
The yearly average Total-P concentration remained about the same at all irrigation
tailwater sites in 1996. The yearly average Total-P concentration decreased from 0.62
mg/l in 1995 to 0.60 mg/l in 1996.
There was one pesticide, Oxadiazon detected .in 1996. The Oxadiazon was from the use
of a herbicide in 1995 that had 1 % Oxadiazon as a constituent. The use of that product
was suspended in August 1995.
PARK HILL NURSERY
Park Hill Nursery is to be commended for lowering the already low nutrient
concentrations in their irrigation tailwater return flow for 1996.
The N03-N concentration at Park Hill Nursery remained below the compliance
agreement average of 10.0 mg/l at all tailwater sites. The yearly N03-N concentration
decreased from 0.94 mg/I in 1995 to 0.76 mg/I in 1996.
The Ammonia Nitrogen sample was taken once at two sampling sites in 1996.
The yearly average Total-P concentration decreased from 0.36 mg/l in 1995 to 0.26 mg/l
in 1996.
Park Hill Nursery had no pesticides detected in its irrigation tailwater sites in 1996.
TABLE OF CONTENT
INTRODUCTION
SAMPLING RESULTS
MAP OF NURSERIES ON THE ILLINOIS RIVER
GREENLEAF NURSERY
Description of Sampling Sites
Figure GL-l Map of Greenleaf Nursery
Sampling Results - Nitrate-Nitrogen
Sampling Results - Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results - Pesticides
Summary
Figures GL-2 to GL-ll
MIDWESTERN NURSERY
Description -of Sampling Sites
Figure MW-l Map of Midwestern Nursery
Sampling Results - Nitrate-Nitrogen
Sampling Results - Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results - Pesticides
Summary
Figures MW-2 to MW-9
PARK HILL NURSERY
Description of Sampling Sites
Figure MW-l Map of Midwestern Nursery
Sampling Results Nitrate-Nitrogen
Sampling Results Total Phosphorus
Sampling Results - Ammonia-Nitrogen
Sampling Results Pesticides
Summary
Figures PH-2 to PH-9
1
1-2
3
4-22
4-5
6
7-9
9-10
10
11
12
13-22
23-36
23
24
25
26-27
27
27-28
28
29-36
37-50
37
38
39-41
41
42
42
42
43-50
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
Greenleaf Nursery N03-N & Total-P Sample Results for 1996
Midwestern Nursery N03-N & Total-P Sample Results for 1996
Park Hill Nursery N03-N & Total-P Sample Results for 1996
Ammonia-Nitrogen (NH4-N) Sample Results for 1996
Pesticide Sample Results for 1996
PAGES
6
5
4
1
16
11
LIST OF TABLES
TABLE PAGE
. GL-1 Description of Sampling Sites at Greenleaf Nursery. 4
GL-2 Average N03-N and TOTAL-P Concentration (ppm) for each
Sampling Site at Greenleaf Nursery from 1992 to 1996. 7
GL-3 The N03-N Concentration in Irrigation Tailwater Site IT-6
after Subtracting The Average N03-N Concentration of the
Two Intake Water Sites 9
GL-4 Pesticide Detection in Tailwater Return Flow at Greenleaf
Nursery for 1996. 11
MW-1 Description of Sampling Sites at Midwestern Nursery. 23
MW-2 Average N03-N and TOTAL-P Concentration for each Sampling
Site at Midwestern Nursery from 1992 to 1996. 25
PH-1 Description of Sampling Sites at Park Hill Nursery. 37,39
PH-2 Average N03-N and TOTAL-P Concentration (ppm) for each
Sampling Site at Park Hill Nursery from 1992 to 1996. 39
111
IV
LIST OF FIGURES
FIGURE PAGE
1 Map of the Illinois River Showing Location of Nurseries in
the Irrigation Tailwater Project. 3
GL-l Map of Greenleaf Nursery. 6
GL-2 Graph of Nitrate-Nitrogen Concentrations in Intake Water
Site IT-I at Greenleaf Nursery for 1994-1996. 13
GL-3 Graph of Nitrate-Nitrogen Concentrations in North
Intake Water Site IT-lb at Greenleaf Nursery for 1994-1996. 14
GL-4 Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-2 at Greenleaf Nursery for 1994-1996. 15
GL-5 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-3a at Greenleaf Nursery for 1994-1996. 16
GL-6 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-6 at Greenleaf Nursery for 1994-1996. 17
GL-7 Graph of Total Phosphorus Concentrations in Intake Water
IT-l at Greenleaf Nursery for1994-1996. 18
GL-8 Graph of Total Phosphorus Concentrations in North Intake
Water Site IT-lb at Greenleaf Nursery for 1994-1996. 19
GL-9 Graph of Total Phosphorus Concentrations in Tailwater Site
IT-2 at Greenleaf Nursery for 1994-1996. 20
GL-lO Graph of Total Phosphorus Concentrations in Tailwater Site
IT-3a at Greenleaf Nursery for 1994-1996. 21
GL-ll Graph of Total Phosphorus Concentrations in Tailwater Site
IT-6 at Greenleaf Nursery for 1994-1996 22
MW-l Map of Midwestern Nursery. 24
MW-2 Graph of Nitrate-Nitrogen Concentrations in Intake
Water Site IT-28 at Midwestern Nursery for 1994-1996 29
MW-3 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-23 at Midwestern Nursery for 1994-1996 30
MW-4 Graph of Nitrate-Nitrogen Concentrations in Tailwater Site
IT-25 at Midwestern Nursery for 1994-1996 31
FIGURE
MW-5
MW-6
MW-7
MW-8
MW-9
PH-l
PH-2
PH-3
PH-4
PH-5
PH-6
PH-7
PH-8
PH-9
LIST OF FIGURES
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-27 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Intake Water
Site IT-28 at Midwestern Nursery for 1994-1996.
Graph of Total Phosphorus Concentrations in Tailwater
Site IT-23 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater
Site IT-25 at Midwestern Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-27 at Midwestern Nursery for 1994-1996
Map of Park Hill Nursery.
Graph of Nitrate-Nitrogen Concentrations in Intake Water
Site IT-16a at Park Hill Nursery for 1994-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-15 at for 1995-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater Site.
IT-18a at Park Hill Nursery for 1995-1996
Graph of Nitrate-Nitrogen Concentrations in Tailwater
Site IT-19b at Park Hill Nursery for 1994-1996.
Graph of Total Phosphorus Concentrations in Intake Water
Site IT-16a at Park Hill Nursery for 1994-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-15 at Park Hill Nursery for 1995-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-18a at Park Hill Nursery for 1995-1996
Graph of Total Phosphorus Concentrations in Tailwater Site
IT-19b at Park Hill Nursery for 1994-1996
v
PAGE
32
33
34
35
36
38
43
44
45
46
47
48
49
50
INTRODUCTION
This is the 1996 Supplement to the 1992 Curtis Report of the Illinois River Irrigation
Tailwater Project involving Greenleaf Nursery, Midwestern Nursery and Park Hill Nursery
that are in operation along the Illinois River and Lake Tenkiller in Cherokee County and
the Oklahoma State Department of Agriculture, Plant Industry and Consumer Services
(PICS).
In 1996, PICS continued monitoring the nurseries by taking samples on a monthly basis
and analyzing the samples for the same parameters, Nitrate-Nitrogen (N03-N), Total
Phosphorus (Total-P) and pesticides, which has been done monthly since 1989.
Beginning in 1995 Ammonia-Nitrogen (NH4--N) was checked periodically to determine a
base level. This was continued in 1996.
Blue Valley Nursery was dropped from the project in 1996 due to inactivity at this
location. If the nursery becomes active in the future then sampling of the irrigation
tailwater return flow will resume.
In 1994, PICS negotiated with each of the nurseries a new compliance agreement which
resulted in lower limits on the nitrate-nitrogen concentration allowed in the irrigation
tailwater return flow of the nurseries.
The 1994 Compliance Agreement with each nursery set the following limits for 1996:
Yearly Average N03-N 10.0 ppm (mg/l)
Individual Sample Maximum N03-N No more than 50% above the
compliance agreements yearly
average on two consecutive
samples, 15.00 ppm (mg/l)
Yearly Average Total-P 1.0 ppm (mg/I)
Individual Sample Maximum No more than 50% above the
compliance agreements yearly
average on two consecutive
samples, 1.5 ppm (mg/l)
Ammonia-Nitrogen NH4-N Checked periodically to
determine base level.
Pesticides 0.0 ppb - Suspend use of a~y
detected after verification In
follow up sample.
1
SAMPLING RESULTS
The sampling results for irrigation tailwater runoff are discussed for each specific
nutrient and pesticide in relation to their compliance agreement with OSDA. The
sample results were looked at under the following conditions:
1. The only statistical calculations conducted on the results were averages.
2. The N03-N and Total-P concentrations of the intake water were not
subtracted from the tailwater samples except where consecutive samples were
at or above the individual sample maximum.
3. Results considered to be outside the data range were discarded.
4. All analysis results are reported in milligrams per liter (mg/l) (same as parts
per million-ppm) for N03-N and Total-P and parts per billion (Ppb) for
pesticides.
5. On numerous occasions, duplicate samples were taken or the lab ran the
analysis more than once. When this occurred the higher sample results were
reported.
6. The owner or manager of each nursery was notified of sample results on a
monthly basis.
7. The pesticide samples that showed a positive detection are listed in tables in
the body of the report. The name of the pesticide is the common name not
the trade name.
8. Graphic presentations concerning intake and irrigation tail water return flow
sampling data are provided in the report. Sampling data for all other sites
are located in the Appendices.
9. Sampling results reported from the lab as 0.0 are below the detectable limit
of 0.20 mg/l (ppm) for Nitrate-Nitrogen (N03-N) and Ammonia-Nitrogen
(NH4-N); 0.02 mg/l (ppm) for Total Phosphorus; 0.0100 ug/l (ppb), for
Organophosphate pesticides and 0.0010 ug/l (ppb) for Organochloride
pesticides.
2
-,G--.t'bson
-- Lake
NA
o 2 3 4 5 Miles
Figure 1
Map of the Illinois River
Showing Location of
Nurseries in the Irrigation
Tailwater Project
10
~. ---
.:
10 1 oJ. V.
•.."•.
f . $"
.( ~
\~ \
\)
~ (' \ J v
\
f -:«
\
~~ Midwestern
Tahlequah ~Nurse
62
---........ ..
~- -- 'Sewage (
_______~ Tr~tme"?,,",
- - -- ... \ v--fJ \ r
Park 'Ft11L-/
Nursery \::-,
.r-r-,
./
-~./
Lake
Tenkiller,
/
51.r--_---'
GREENLEAF NURSERY
Greenleaf Nursery is approximately 460 acres, located on hilly land directly adjacent to
Lake Tenkiller on Oklahoma State Highway 82 in Cherokee County.
Irrigation water is pumped from the lake and applied to container grown trees and
shrubs through a stationary overhead sprinkler system.
Fertilization is done mostly by using plastic encapsulated slow release type fertilizer
which is either mixed into the soil media or applied to the top of the soil by hand.
In 1996 Greenleaf Nursery continued the construction of retention basins with pumping
facilities in order to recycle their irrigation tailwater. This construction has resulted in a
large amount of dirt and rock being moved, which may have contributed to some of the
elevated levels of nitrate-nitrogen in some irrigation tailwater return flow samples.
Figure GL-1 is a map showing the sampling sites at Greenleaf Nursery for 1996.
DESCRIPTION OF SAMPLING SITES.
Table GL-1 lists and describes the sampling sites at Greenleaf Nursery for 1996.
TABLE GL-l: Description of Sampling Sites at Greenleaf Nursery
SITE DESCRIPTION
IT-1 Main water intake site. Located on the southeast side of the nursery
and down the bank to Lake Tenkiller. The samples are taken from the
area around the float where the pumps are located.
IT-1b Second intake site situated on the northeast side of the nursery down
the bank to Lake Tenkiller. The samples are taken from around the
float where pumps are located.
IT-2 Irrigation tail water runoff site located on the southeast side of the
nursery approximately 200 feet south of the main intake float on Lake
Tenkiller. The samples are taken as the water leaves the nursery
property.
IT-3a Irrigation tailwater site located at the detention basin near the main
entrance to the nursery. The samples are taken down the dam
embankment where the overflow pipe empties.
IT-4 Ephemeral stream on the northeast side of the main container area.
This site is located along the dirt road on the north edge of the
nursery. The samples are taken near the pipe after going under the
road and before entering Greenleaf Nursery's property.
4
TABLE GL-l: Description. of Sampling Sites at Greenleaf Nursery Con't.
IT-5 Ephemeral stream entering the nursery near the upper detention basin
from the outside. This site is located on the dirt road along the north
boundary of Greenleaf Nursery's property. The samples are taken near
pipe that goes under the road and before entering the nursery's
property. Sampled when sufficient runoff is present
IT-6 Irrigation tailwater runoff site located on the southeast side of the
nursery. The samples are taken 100 ft. below the last confluence of
nursery tailwater runoff.
IT-11 Well is located south of the propagation greenhouses near the entrance
to Greenleaf Nursery. The samples are taken from hose bibb inside
the well house.
5
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Greenleaf
Nursery
400 Acres
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Figure GL-1
Map showing the location of the sampling sites at Greenleaf Nursery for 1996.
SAMPLING RESULTS
Sample results for site IT-4 and site IT-5 see Appendix - A.
NITRATE-NITROGEN (N03-N)
The 1994 compliance agreement with Greenleaf Nursery set the yearly average N03-N
concentration for 1996 at 10.0 ppm (mg/l) and the maximum limit (50% greater than the
yearly average) at 15.0 ppm (mg/l) on two consecutive sampling dates after subtracting
the intake water N03-N concentration.
The N03-N concentration in 1996 was lower than in 1995 at site IT-2 and higher at
the other two tailwater sites. Site IT-6 average of 13.12 mg/l exceeds the compliance
agreement average of 10.00 ppm (mg/l). The highest concentrations continued to occur
during the late spring and summer months. (Fig. GL-4, GL-5, and GL-6)
There were three consecutive samples that exceeded the compliance agreement maximum
of 15.00 mg/l in 1996; after subtracting the average of the two intake water sites N03-
N concentrations. These occurred at site IT-6 in August, September and October with
29.26 mg/l (31.6 - 2.34), 16.43 rng/l (16.43 - 0.0) and 21.54 mg/l (21.88 - 0.34) respectively
(Table - GL-3). Greenleaf Nursery was contacted to find out the cause of these
elevations. The elevated N03-N concentrations were due to the movement of dirt
during the construction of retention basins in addition to the use of new fertilizer
products and in correcfing a fertilizer deficiency problem.
The yearly average N03-N concentration in the tailwater sites increased to 10.26 mg/l 10
1996 (Table GL-1). This is an increase of 46.78% from the 1995 concentration.
TABLEGL-2: Average N03-N and TOTAL-P Concentrations (mg/l) for each
Sampling Site at Greenleaf Nursery from 1992 to 1996.
SAMPLING SITE N03-N mg/l TOTAL-P mg/l
92 93 94 95 96 92 93 94 95 96
IT-1 1.08 1.11 1.10 0.81 1.18 0.10 0.11 0.16 0.09 0.12
IT-1b 0.97 1.04 0.08 0.11
IT-2 8.58 6.24 10.53 10.13 8.65 1.13 1.09 1.37 1.29 0.8
IT-3a 15.65 11.85 6.97 6.56 9.01 0.46 0.61 0.43 0.68 0.51
IT-6 14.48 9.30 8.57 4.27 13.12 0.44 0.60 0.44 0.51 0.41
IT-II 0.20 0.42 0.15 0.44 0.62 0.12 0.03 0.07 0.05 0.03
IT-12 16.68 12.09 ---- 1.18 0.66 -- --
Tailwater
Yearly Avg. 13.85 9.87 8.69 6.99 10.26 0.80 0.74 0.75 0.83 0.57
Compliance
Ag.Avg. 28.0 18.5 15.5 14.5 10.00 1.0 1.0 1.0 1.0 1.0
7
Site IT-l- Intake
The N03-N concentrations at site IT-1 ranged from 0.0 mg/l in October (below the
detectable limit of 0.2 mg/l) to 2.34 mg/l in August (Fig. GL-2 and Appendix - A).
The yearly average N03-N was 1.18 mg/I (Table GL-2).
Site IT-lb - SecondIntake
The N03-N concentrations at site IT-lB ranged from 0.0 mg/l (below the detectable
limit of 0.2 mg/l) in July to 2.33 mg/l in December (Fig. GL-3 and Appendix - A) with
a seasonal low occurring in the summer months.
The yearly average N03-N was 1.04 mg/l (Table GL-2).
Site IT-2.
The N03-N concentrations at site IT-2 (the waterfall) ranged from 1.57 mg/l in October
to 19.74 mg/l in May. Two samples, one taken in May and the other taken in August
were above 15.0 mg/l (the compliance agreement average) (Fig. GL-4 and Appendix-
A). However, these were not consecutive samples.
The yearly average N03-N concentration decreased from 10.13 rng/l in 1995 to 8.65
mg/l in 1996 (Table GL-2 and Fig. GL-4). This is a decrease of 14.61% from 1995.
Site IT-3a
The N03-N concentration for site IT-3a ranged from a low of 0.0 mg/l (below the
detectable limit of 0.2 mg/l) in June to a high of 14.64 mg/l in July (Fig. GL-5 and
Appendix - A). No sample exceeded the compliance agreement maximum of 15.0 mg/I.
The yearly average N03-N concentration increased from 6.97 mg/l in 1995 to 9.01 mg/l
in 1996 (Table GL-2 and Fig. GL-5) This is an increase of 37.35% from the 1995
yearly average. However, this was still below the compliance agreement average of 10.0
mg/I.
Site IT-6
The N03-N concentration for site IT~ ranged from a low of 0.0 mg/l (below the
detectable limit of 0.2 mg/I) in February to a high of 33.47 mg/l in June (Fig. GL~
and Appendix - A). There were three samples that exceeded the compliance agreement
maximum of 15.0 ppm (mg/I) on consecutive dates after subtracting the intake waters
N03-N concentration (Table GL-3).
As discussed earlier these elevations were due to movement of dirt in the construction of
detention basins, and the use of different fertilizers in trying to solve a fertilizer
deficiency problem.
The yearly average N03-N concentration increased from 4.27 mg/l in 1995 to 13.12 mg/l
in 1996 (Table GL-2 and Fig. GL~). This represents a 207% increase from the 1995
yearly average.
8
TABLE GL-3 The N03-N Concentration in Irrigation Tailwater Site
IT-6 after Subtracting The Average N03-N Concentration of the
Two Intake Water Sites.
DATE IT-16 mg/l Avg. Intake mg/l Adjusted mg/l
5/20 15.62 1.73 13.89 below compliance maximum
6/25 33.47 0.25 33.22 above compliance maximum
8/27 31.6 2.34 29.26 above compliance maximum
9/9 16.43 a 16.43 above compliance maximum
10/15 21.88 0.34 21.54 above compliance maximum
Site IT-U WATER WELL
The N03-N concentrations ranged from a low 0.34 mg/l in September to a high of 1.19
mg/l in October (Appendix - A).
The yearly average was 0.62 mg/l in 1995 (Table GL-2)
TOTAL PHOSPHORUS (TOTAL-P)
The 1994 compliance agreement set a yearly average Total-P concentration of 1 mg/l
and a maximum limit of not greater than 50% above the yearly average or 1.5 mg/l on
two consecutive sampling dates after subtracting the intake water Total-P concentration.
All irrigation tailwater sites had a lower yearly average Total-P concentration in 1996
than 1995. Also, no site exceeded the compliance agreement average of 1 ppm (mg/l).
Greenleaf Nursery's overall yearly average Total-P concentration for irrigation tailwater
sites for 1996 is 0.57 mg/l which is 0.26 mg/l or 31% lower than the 0.83 mg/l in
1995.
Site IT-l
The Total-P concentration at the first intake site ranged from 0.02 mg/l in October to
0.31 mgll in November. No sample was taken in March (Fig. GL-7 and Appendix-A).
The yearly average is 0.12 mg/l (Table GL-2 and Fig. GL-7).
Site IT-IB
The Total-P concentration at the second intake site ranged from 0.02 mg/l in March to
0.50 mg/l in November (Fig. GL-8, Appendix - A). The yearly average is 0.11 mg/l
(Table GL-2 and Fig. GL-8).
9
Site IT-2
The Total-P concentration at irrigation tailwater site IT-2 ranged from a low of 0.28
mg/l in November to a high of 1.18 mg/l in March (Fig. GL-9 and Appendix - A).
The yearly average concentration for Total-P is 0.80 mg/I. This is below the
compliance agreement average of 1.0 mg/l (Table GL-2 and Fig. GL-9). This represents
a 38 % decrease from 1995.
Site IT-3a
The Total-P concentration at irrigation tailwater site IT-3a ranged from a low of 0.0
mg/l (below the detectable limit of 0.02 mg/l) in June to a high of 0.80 mg/l in April
(Fig. GL-lO and Appendix - A).
The yearly average concentration for Total-P is 0.51 mg/l which is below the
compliance agreement average of 1.00 mg/l (Table GL-2 and Fig. GL-lO). This
represents a decrease of 25% from the 1995 average of 0.68 mg/l.
Site IT~
The Total-P concentration at irrigation tailwater site IT-6 ranged from a low of 0.02
mg/l in March to a high of 1.24 mg/l in April. (Fig. GL-ll and Appendix - A) These
are below the compliance agreement maximum of 1.5 mg/l .
The yearly average concentration for Total-P is 0.41 mg/l (Table GL-2,). This is a
decrease of 20 % from the 1995 average of 0.51 mg/l.
Site IT-U Water Well
The Total-P ranged from a low of 0.0 mg/l (below the detectable limit of 0.02 mg/l) in
May to a high of 0.13 mg/l in October (Appendix - A). The yearly average was 0.05
mg/l.
AMMONIA-NITROGEN NH4-N
Ammonia Nitrogen (NH4-N) was checked once this year at site IT-1 and IT-6 There
has not been any maximum NH4-N concentrations set for the nurseries at this time.
Samples were taken during the primary irrigation season of April to September.
Site IT-l
One sample was taken In August with an NH4-N concentration of 0.36 mg/l (Appendix
D)
Site IT~
One sample was taken at this site. The NH4-N concentration was 9.44 mg/l in August
(Appendix D).
10
PESTICIDES
Greenleaf Nursery had Diazinon and Oxadiazon detected at irrigation tailwater site IT-2
and only Oxadiazon at site IT-3a and IT-6 in 1996. Table GL-4 lists the pesticides
detected, the date and site of the detection, and the concentration detected (Appendix E).
TABLE GL-4: Pesticide Detections in TailwaterReturn Flow at
Greenleaf Nursery For 1996
SITE DATE SAMPLE # COMMON NAME CONCENTRATION
in Parts Per
Billion (ppb)
IT-2
02-26-96 SO-477-P DIAZINON 1.907
08-27-96 SO-136-P DIAZINON 1.69
05-20-96 SO-686-P OXADIAZON 1.56
06-25-96 SO-796-P OXADIAZON 0.192
07-22-96 SO-016-P OXADIAZON 0.107
08-27-96 SO-27-96 OXADIAZON 0.979
IT-3a
02-26-96 SO-487-P OXADIAZON 0.977
04-22-96 SO-615-P OXADIAZON 0.85
05-20-96 S0-698-P OXADIAZON 0.56
08-27-96 SO-145-P OXADIAZON 0.471
IT-6 05-20-96 SO-692-P OXADIAZON 0.21
06-25-96 SO-802-P OXADIAZON 0.062
08-27-96 SO-138-P OXADIAZON 1.048
OXADIAZON
Oxadiazon was detected at all three sites in 1996. Four times at irrigation
tailwater site IT-2 and IT-3a, and three times at site IT-6. The concentration
ranged from 0.062 ppb in June at site IT-6 to 1.56 ppb in May at site IT-2
(Table GL-4 and Appendix E). This product has not been used by this nursery
since 1990.
DIAZINON
Diazinon was detected twice, February and August, at site IT-2 in 1996. Follow
up sampling did not detect any diazinon in the irrigation tailwater flow samples
(Table GL-4 and Appendix E).
11
SUMMARY
The 1994 compliance agreement lowered the yearly average N03-N concentration from
14.5 ppm (mg/l) in 1995 to 10.0 ppm (mg/I) in 1996. The maximum limit was lowered
to 15.0 ppm (mg/I) (50% greater than the yearly average on two consecutive sampling
dates after subtracting the intake water N03-N concentration) from the 21.75 ppm (mg/I)
in 1995.
The yearly average N03-N concentration decreased at tailwater site IT-2 and increased
at sites IT-3a and IT-6.
In 1996 the yearly average N03-N concentration increased from 6.99 mg/I in 1995 to
10.26 mg/I. This is an increase of 46.8 %.
Greenleaf Nursery had eight samples in 1996 that exceeded the compliance agreement
maximum for individual samples in regard to the N03-N concentrations.
Site IT-6 had N03-N concentrations exceeding the compliance agreement maximum of
15.0 mg/I on four (4) different sampling dates (three of these were consecutively) after
subtracting the intake water N03-N concentration). Site IT-3a had no samples that
exceeded the compliance agreement maximum. These elevations were due to movement
of dirt in the construction of detention basins, and the use of different fertilizers in
trying to solve a fertilizer deficiency problem.
Ammonia Nitrogen (NH4-N) samples were taken once at two sampling sites in 1996.
The average Total-P concentration was lower at all irrigation tailwater sites in 1996.
The overall average Total-P decreased from 0.83 mg/l in 1995 to 0.57 rng/l in 1996. This
is a decrease of 31.3%.
Site IT-2 lowered the Total-P concentration from 1.29 mg/l to 0.8 mg/l, a reduction of
38 % from the 1995 concentration.
There were two (2) different pesticides detected in 1996 in samples from the three
tailwater sites (Appendix E). Oxadiazon was detected 11 times at concentrations from
1.56 ppb to 0.062 ppb. This product has not been used by this nursery since May
1990. Diazinon was detected twice at site IT-2 at concentrations less than 2 ppb.
12
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SAMPLING DATES 1994-1996
Figure-GL-7 Graph of the Total-P Concentration in Intake Water Site IT-l at Greenleaf
Nursery for 1994-1996
IT-lb
• SAMPLES
10
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9
8
7
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SAMPLING DATES 1995-1996
Figure GL-8 Graph of the Total-P Concentration in Intake Water Site IT-lb at Greenleaf Nursery
for 1994-1996
'§, 6
E
Il..
~ 5
~o•...4
IT-2
_SAMPLES - - COMP-MAX - -COMP-AV - - YEARLY-AV
10
-
-
=: . i--- - .- -- ---------_ .. - ""' . -- . ----- .•... - -- - - - •.... -- .'.-. --.- -----, --- .- - - - - - - -- - -If -- ---------------- I -- ~......----- .----.--.....--. • • I.I I 111.1.1
9
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SAMPLING DATES 1994-1995
Figure GL-9 Graph of the Total-P Concentration in Irrigation Tailwater Site IT-2 at Greenleaf Nursery
for 1994-1996
IT-3a
_SAMPLES - - COMP-MAX - -COMP-AV - - YEARLY-AV
10 ,------ ---
7~---------
9 ~---------
8-·~---------------------------------------------~
~ 6 -1--------
E e,~
5~-------------------------
~o~4~--------------------------------------------~
3~--------------------------------------------~
2~--------------------------------------------~
SAMPLING DATES 1994-1996
Figure GL-I0 Graph of the Total-P Concentration in Irrigation Tailwater Site IT-Sa at Greenleaf
Nursery for 1994-1996
IT-6
- SAMPLES - - COMP-MAX - -COMP-AV - - YEARL Y-AV
10r--------------------------------------------------------------------------------------------------,
91----------------------
3 t-----
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- -- --
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SAMPLING DATES 1994-1996
Figure GL-ll Graph of the Total-P Concentration in Irrigation Tailwater Site IT-6 at Greenleaf
Nurserv for 1994-1996